Ever wonder what all the Italian words and phrases on Ducati bikes mean? Terms like "Desmodromic", "Desmosedici", and "Testastretta"? Me too. This got me into some etymological research today to find out.
Desmodromic
Desmodromic, no matter how you slice it, is not an Italian word. So, I had to go back a little further in time.
Oxford Dictionary
esmo - (Greek) - bond, fastening, chain, ligature, an element in scientific words of Greek derivation.Dromic - (Greek) - course, race course. Of pertaining to, or of the form of a race-course; applied to the basilican type of Eastern Churches from its resemblance to the plan of a race course.Latin Dictionary:
Dromas - Able to run well.Dromos - An open space with room to move freely, a parade ground, etc. Also, pertaining to the race-course of the Spartans."Desmodromic" is not strictly a mechanical term either. You find the "desmo" prefix a lot in biology and other sciences, where we can see a common relation to "being connected". For example, a Desmosome is a filament-like substance that adheres cells together. Likewise, "Desmoplakin" is the protein associated with this intercellular junction. A zoological term that is most closely analogous to Ducati desmo valves would be "Desmopelmous", a type of bird foot in which the hind toe cannot be bent independently because planter tendons are united. To get the idea, hold your hand fixed in a "C" shape and rock it back and forth at the wrist.
It is clear that "Desmo" refers to something that is connected or "works together". Traditional spring valves obviously have two different mechanisms to open and close the valve (they are not "connected"), whereas Ducati systems have one. Hence, "desmodromic", or "working in unison and related to racing" or "working in unison and able to run well".
Supposedly, from what I'm reading, the term "desmodromic" was coined by the French and later borrowed by Italy.
Desmosedici
This one became obvious, once I broke the word in half and used Google Translations.
http://www.google.com/translate_t?sl=it&tl=en&q=sedici
"Sedici" means "16". This refers to the 16 Desmo valves of the 4-cylinder Desmosedici engine.
Testastretta
Again, Google Translating the entire word yielded nothing. The revelation came in splitting the word in two:
Testa - "Head"Stretta - "Close". Babelfish gave me "tightened". I found another translation of "narrow".Testastretta means "close head", "tightened head", or "narrow head".
Does this mean that the two heads of the engine were brought closer together - perhaps a reduction in cylinder angle? No. The cylinder configuration of Ducati twins has always been at a 90-degree angle. "Testastretta" refers to each head. Ducati first used the term "Testastretta" in 1984 with the advent of their new race engine at the time. An engine has intake valves and it has exhaust valves. There is an angle between these valves, as the camshaft sits between them. Early desmo valves in the 50's had a very wide angle, at around 90 degrees. This made for a inefficient "house-shaped" combustion chamber. Ducati later reduced this angle to 60 degrees and even as little as 40 degrees (likely even less these days). So, the Testastretta motor had a significantly reduced angle between the valves. This made for a much more square combustion chamber, more compact, and consequently more efficient at burning aerated fuel, i.e., more power! This reduce valve angle made each head narrower, hence "Narrow Head".
Let's just say this. If an Italian gentleman calls you a "testamerde", you have done something to piss him off.
Testastretta Evoluzione
The latest incarnation of the Testastretta engine of course came in 2007 on the Ducati 1098, the Testastretta Evoluzione, in English the "Narrow Head Evolution" - Ducati's crowning achievement, and the lightest, most powerful two-cylinder production engine ever made.
Corse
This one was easy. It simply means "race".
http://www.google.com/translate_t?sl=it&tl=en&q=corse
Corsa
Why does Pirelli spell it with an "a" on their tires? I get "ride" from Google Translations:
http://www.google.com/translate_t?sl=it&tl=en&q=corsa
Perhaps, it's the verb form of "race" - the act of racing or riding - whereas "corse" with an "e" is the noun form, the race itself.
Desmo History
I discovered (a discovery for me anyway) a Dutch author of the book "Desmodromie", Henk Cloosterman, a 15-year "professor" in Desmodromology. He spent 5 years writing the Desmo patent study, and 12 years creating a collection of working models for every basic type of Desmodromic valve gear. There is some great information on this site, and some fascinating pictures and videos of a number of different Desmo valve arrangements throughout history:
http://members.chello.nl/~wgj.jansen/
His book is out of print, but he has preserved several full chapters in PDF form on the site. It's amazing the number of different Desmo systems that exists, from various manufacturers, over the last 122 years! The first were mentioned in patents in 1896! Now that is having some history beneath your arse!
Ducati's first use of Desmodromic systems can be traced back to 1954, with the hiring of legendary Chief Engineer, Fabio Taglioni. The technology was naturally first used and developed on the race track with the 125 Desmo Ducati, essentially Ducati's 125 Grand Prix with a Desmo-equipped engine in it. The performance gains were quickly realized. The 125 Grand Prix was producing 16 HP at 11,500 RPM at the time, while the 125 Desmo was cranking out a whopping 19 HP at 12,500 RPM and could safely rev to 15,000 RPM! The 125 Desmo Ducati won its first race at the 1956 Swedish G.P. at Hedemora, lapping all the other cycles, but then its rider, Gianni Degli Antoni, died during the practice for the next race, the Italian G.P. of Monza. (That puts a slight damper on your ground-breaking win, doesn't it?)
Ducati's first production Desmo system was in 1968, with the advent of the Mark 3 Desmo 350, also a single-cylinder motorcycle. The Mark 3 D's were the first production motorcycles in the world with a Desmodromic head.
1972 saw Ducati's first Desmodromic twin-cylinder bike, the timeless 750 Super Sport, toted by many as one of the most beautiful bikes ever made. (I could not agree more.) Thus began Ducati's commitment to 90-degree, Desmodromic L-Twins, that still exist in 98% of the Ducati line to this day.
There is a nice, digest-form biography on the Ducati site about this amazing engineer, Fabio Taglioni: a Legend. The man designed over 1,000 engines! Now that's commitment to excellence! Interesting to also see where the "prancing horse" emblem came from.
Desmodromic
Desmodromic, no matter how you slice it, is not an Italian word. So, I had to go back a little further in time.
Oxford Dictionary
esmo - (Greek) - bond, fastening, chain, ligature, an element in scientific words of Greek derivation.Dromic - (Greek) - course, race course. Of pertaining to, or of the form of a race-course; applied to the basilican type of Eastern Churches from its resemblance to the plan of a race course.Latin Dictionary:Dromas - Able to run well.Dromos - An open space with room to move freely, a parade ground, etc. Also, pertaining to the race-course of the Spartans."Desmodromic" is not strictly a mechanical term either. You find the "desmo" prefix a lot in biology and other sciences, where we can see a common relation to "being connected". For example, a Desmosome is a filament-like substance that adheres cells together. Likewise, "Desmoplakin" is the protein associated with this intercellular junction. A zoological term that is most closely analogous to Ducati desmo valves would be "Desmopelmous", a type of bird foot in which the hind toe cannot be bent independently because planter tendons are united. To get the idea, hold your hand fixed in a "C" shape and rock it back and forth at the wrist.
It is clear that "Desmo" refers to something that is connected or "works together". Traditional spring valves obviously have two different mechanisms to open and close the valve (they are not "connected"), whereas Ducati systems have one. Hence, "desmodromic", or "working in unison and related to racing" or "working in unison and able to run well".
Supposedly, from what I'm reading, the term "desmodromic" was coined by the French and later borrowed by Italy.
Desmosedici
This one became obvious, once I broke the word in half and used Google Translations.
http://www.google.com/translate_t?sl=it&tl=en&q=sedici
"Sedici" means "16". This refers to the 16 Desmo valves of the 4-cylinder Desmosedici engine.
Testastretta
Again, Google Translating the entire word yielded nothing. The revelation came in splitting the word in two:
Testa - "Head"Stretta - "Close". Babelfish gave me "tightened". I found another translation of "narrow".Testastretta means "close head", "tightened head", or "narrow head".
Does this mean that the two heads of the engine were brought closer together - perhaps a reduction in cylinder angle? No. The cylinder configuration of Ducati twins has always been at a 90-degree angle. "Testastretta" refers to each head. Ducati first used the term "Testastretta" in 1984 with the advent of their new race engine at the time. An engine has intake valves and it has exhaust valves. There is an angle between these valves, as the camshaft sits between them. Early desmo valves in the 50's had a very wide angle, at around 90 degrees. This made for a inefficient "house-shaped" combustion chamber. Ducati later reduced this angle to 60 degrees and even as little as 40 degrees (likely even less these days). So, the Testastretta motor had a significantly reduced angle between the valves. This made for a much more square combustion chamber, more compact, and consequently more efficient at burning aerated fuel, i.e., more power! This reduce valve angle made each head narrower, hence "Narrow Head".
Let's just say this. If an Italian gentleman calls you a "testamerde", you have done something to piss him off.
Testastretta Evoluzione
The latest incarnation of the Testastretta engine of course came in 2007 on the Ducati 1098, the Testastretta Evoluzione, in English the "Narrow Head Evolution" - Ducati's crowning achievement, and the lightest, most powerful two-cylinder production engine ever made.
Corse
This one was easy. It simply means "race".
http://www.google.com/translate_t?sl=it&tl=en&q=corse
Corsa
Why does Pirelli spell it with an "a" on their tires? I get "ride" from Google Translations:
http://www.google.com/translate_t?sl=it&tl=en&q=corsa
Perhaps, it's the verb form of "race" - the act of racing or riding - whereas "corse" with an "e" is the noun form, the race itself.
Desmo History
I discovered (a discovery for me anyway) a Dutch author of the book "Desmodromie", Henk Cloosterman, a 15-year "professor" in Desmodromology. He spent 5 years writing the Desmo patent study, and 12 years creating a collection of working models for every basic type of Desmodromic valve gear. There is some great information on this site, and some fascinating pictures and videos of a number of different Desmo valve arrangements throughout history:
http://members.chello.nl/~wgj.jansen/
His book is out of print, but he has preserved several full chapters in PDF form on the site. It's amazing the number of different Desmo systems that exists, from various manufacturers, over the last 122 years! The first were mentioned in patents in 1896! Now that is having some history beneath your arse!
Ducati's first use of Desmodromic systems can be traced back to 1954, with the hiring of legendary Chief Engineer, Fabio Taglioni. The technology was naturally first used and developed on the race track with the 125 Desmo Ducati, essentially Ducati's 125 Grand Prix with a Desmo-equipped engine in it. The performance gains were quickly realized. The 125 Grand Prix was producing 16 HP at 11,500 RPM at the time, while the 125 Desmo was cranking out a whopping 19 HP at 12,500 RPM and could safely rev to 15,000 RPM! The 125 Desmo Ducati won its first race at the 1956 Swedish G.P. at Hedemora, lapping all the other cycles, but then its rider, Gianni Degli Antoni, died during the practice for the next race, the Italian G.P. of Monza. (That puts a slight damper on your ground-breaking win, doesn't it?)
Ducati's first production Desmo system was in 1968, with the advent of the Mark 3 Desmo 350, also a single-cylinder motorcycle. The Mark 3 D's were the first production motorcycles in the world with a Desmodromic head.
1972 saw Ducati's first Desmodromic twin-cylinder bike, the timeless 750 Super Sport, toted by many as one of the most beautiful bikes ever made. (I could not agree more.) Thus began Ducati's commitment to 90-degree, Desmodromic L-Twins, that still exist in 98% of the Ducati line to this day.
There is a nice, digest-form biography on the Ducati site about this amazing engineer, Fabio Taglioni: a Legend. The man designed over 1,000 engines! Now that's commitment to excellence! Interesting to also see where the "prancing horse" emblem came from.